Cylindrifflugia periurbana  González-Miguéns et al., 2023

Diagnosis: General shell shape is cylindrical-pyriform, with a circular section and composed of exogenous material (usually sand grains) attached with an organic cement. Aperture diameter equal to or smaller than the width of the shell, but not larger. Rounded fundus, with a spine.

Dimensions: González-Miguéns et al. (2023): Shell length 249.8–264.6 μm (mean 255.25 μm, n=4); shell width 104.3–118.9 μm (mean 112.9 μm, n=4); aperture 55–61.6 μm (mean 59.7 μm, n=4); aboral spine, mean 26.41 μm (n=4)

Habitat: Freshwater sediment, collected in the eutrophic pond of a urban park.

Geographical distribution: Type locality: Spain, Madrid, Parla (40°14′ N, 3°46′ W). Pond in the Parque del Universo.

Remarks: Cylindrifflugia periurbana can be diagnosed by its specific mtDNA (COI) and nuclear (SSU rRNA) sequences and by its phylogenetic placement. Differs morphologically from Cylindrifflugia lanceolata from its overall pyriform shell shape (thinner next to the aperture and wider fundus) and the presence of a spine. It is also considerably smaller than Cylindrifflugia acuminata (Ehrenberg, 1838), for which lengths of 333 μm (1/3 mm) have been reported.